and others from the group descended the stairs and...

and others from the group descended the stairs and congregated there for a while before heading back up and observing that Tower One had disappeared as well.

"Some subhuman animals, if you can even call them animals, had changed our world forever," Hingson said.

Today, Hingson has his own company and travels the world, motivating people and showing them how, through teamwork, they can accomplish tasks differently. He travels with a different guide dog, however, as Roselle died June 26 of disorders perhaps tied to the toxic dust she inhaled that day.

Hingson said he carries with him many lessons from 9/11, one of which goes hand in hand with his disability: Don't let sight get in the way of your vision.